A drill stop sleeve and a dental drill device comprising a dental drill and a drill stop sleeve are known from U.S. Pat. No. 6,514,258 B1. Said document discloses a dental drill that has a drilling end and a cylindrical shank part. At an end area of the shank part directed toward the drilling end, it is provided with a cuff-like thickened area that has a greater diameter than the bore diameter of the dental drill. At one of its end faces, the drill stop sleeve has an abutment surface and, adjoining the other end face, a clamp area intended to engage around the thickened area. In the clamp area, the drill stop sleeve has the greatest external diameter, which is formed by several resilient clamp fingers. These are formed by gaps extending in the longitudinal direction of the drill stop sleeve and open at the end. The drill stop sleeve can be pushed onto the dental drill from the direction of the drilling end, by which means the clamp area comes to engage with the thickened area in the manner of a snap-fit closure.
In order to drill a hole with a defined drilling depth, U.S. Pat. No. 6,514,258 B1 discloses drill stop sleeves of different lengths that can be fitted onto the dental drill of given length. The drilling depth of the dental drill device is in each case defined by the distance between the drilling end and the abutment surface of the fitted drill stop sleeve. Said document also discloses that dental drills with two different bore diameters can be used. As regards the material used for the drill stop sleeve, the document states that rigid, stiff materials such as metal or plastic can be used.
A disadvantage of the drill stop sleeve according to this prior art has proven to be that the view of the drilled hole is partially obstructed by the drill stop sleeve, in particular just before the abutment surface reaches the bone or the tissue or material surrounding the drilled hole. A further disadvantage has proven to be that several finger-like clamp elements are formed in the clamp area, making production complicated and therefore expensive. Another disadvantage has proven to be that the drill stop sleeve has the greatest external diameter in the clamp area, which also obstructs the view.
It would be desirable to provide a drill stop sleeve and a dental drill device that do not have the disadvantages mentioned above. Also desirable is a packaging that facilitates the handling of the drill stop sleeves.